1. Preheat oven to 350°F. Prepare cake mix according to package directions.
2. Stir in apples, pour batter into well greased and floured 13 x 9-inch baking pan. Bake 30 to 35 minutes or until toothpick comes out clean.
3. In large bowl, combine Eagle Brand® milk and sour cream; mix well. Stir in lemon juice.
4. Remove cake from oven; spread sour cream mixture evenly over hot cake. Return cake to oven, bake 5 minutes or until set. Sprinkle cinnamon, if using. Cool, chill. Store leftovers covered in refrigerator. 

From www.eaglebrand.com via www.nancyskitchen.com